Universal Access To All Knowledge
Home Donate | Store | Blog | FAQ | Jobs | Volunteer Positions | Contact | Bios | Forums | Projects | Terms, Privacy, & Copyright
Search: Advanced Search
Anonymous User (login or join us)
Upload

Reply to this post | See parent post | Go Back
View Post [edit]

Poster: kc0dhb Date: Nov 5, 2005 2:49pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

That file worked quite nicely (little grainy, but sound was good).
Just out of curiousity, what did you change?

I also rewrote my script to allow for you to change the bit rate when you run the program.

I also found that 368kbps works very well for cartoons (color too)

Kyle

Perl script follows
---
#!/usr/bin/perl
#Written by Kyle Byerly
#required software
# ffmpeg compiled with --enable-mp3lame --enabled-faad --enable-faac --enable-xvid buildflags
# instructions for ubuntu at http://po-ru.com/diary/fixing-ffmpeg-on-ubuntu/
# the original script was one i took from iSquint for Mac, but since my Linux box is quite
# a bit faster than an aging powerbook...

print "When you execute this script, enter the files you want after the script on the commandline.\n";
print "Example.\n";
print "\t./video2ipod.pl /home/kyle/dvd/*.avi\n";
print "This will place files with the exact same name with 2300kbps.ipod.mp4 appended to the filename, if 2300 was the bitrate\n";
print "Right now it only makes files optimized for the iPod screen\n";

print "Please enter the bitrate that you would like, less than 2500, default of 2300: ";
chomp($bitrate = );
#set default bitrate of 2300
if ($bitrate == "\n") {
$bitrate = 2300;
}
#if the bitrate is greater than 2500 you can still encode, but why?
if ($bitrate > "2500") {
print "This is greater than an iPod will play...just so you know.\n";
}
if ($bitrate < 256) {
print "Output may be ok, but not so good on fast moving parts...recommend you try a higher bitrate.\n"
}

foreach (@ARGV) {
system < ffmpeg -i "$_" -s 320x240 -vcodec xvid -g 300 -qmin 2 -b $bitrate -acodec aac -ar 44100 "$_"."$bitrate"kbps.ipod.mp4 >;
}
----

Reply to this post
Reply [edit]

Poster: A/V Geek Skip Date: Nov 5, 2005 11:58pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

The Internet Archive has been working on fixing the MPEG-4 derivation parameters, so I'm going back and re-deriving the older films to see if the audio squeak problem has been fixed.

So, if you and other iPod users could help verify that these files are fixed, I can start re-deriving all the feature films.

What was changed? I dunno. Tracey at the IA worked really hard to fix MPEG-4 transcoding parameters a couple of months ago.

Here's some files to check out:
http://www.archive.org/download/sing_a_song_of_six_pants/sing_a_song_of_six_pants_256kb.mp4
http://www.archive.org/download/feud_maker/feud_maker_256kb.mp4
http://www.archive.org/download/drugs_are_like_that/drugs_are_like_that_256kb.mp4
http://www.archive.org/download/why_doesnt_cathy_eat_breakfast/why_doesnt_cathy_eat_breakfast_256kb.mp4

Skip

Reply to this post
Reply [edit]

Poster: Administrator, Curator, or Stafftracey pooh Date: Nov 6, 2005 2:26am
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

Yay! A new mp4 success on ipod, woot! 8-D

Yes, so we had an intern who brilliantly figured out how
to solve most of our audio problems by simply using
"mplayer" to dump the audio as a stereo WAV track.

Since mplayer can play pretty much anything, this meant
that most of our "audio problems" suddenly got fixed.
Better yet, instead of the 3-4 audio pass encodings just
to get the WAV/PCM format, it's all done in one quick
mplayer command now.

I then hooked it all up, fixed up some "encode to mpg audio"
settings, and there it is!

Lastly, I tossed 15 of the worst and most difficult items
I knew at it and rederived them (they had horrible or
completely gone audio in the derived mp4s). To my utter
shock and delight, all worked.

As I personally love moving images, I'm glad we finally got
a lot of this audio stuff fixed!
mp4 files aren't the easiest to "get right" -- they're not
like the supereasy MPG1 and MPG2 formats, unfortunately.

--tracey, webmaster,
and occassional movie geek and cheerleader

Reply to this post
Reply [edit]

Poster: Supersensor Date: Feb 20, 2006 2:10pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

I have also been having trouble with my iPod video in two ways, but maybe this will help:
1. Some films that I used iSquint to convert (I have grabbed some of the larger mpeg files that need conversion before they are dropped into iTunes,) and they have a flaw in that the video/audio will freeze, and then restart with no audio. Apparently this is a flaw with the iPod 1.1 updater.
2. Some of the 256k/Mp4 files will play fine in Quicktime or in iTunes, but on the iPod they produce a clicking/digi-distortion periodically. This may also be related to the updater issue, BUT, I had no trouble with the "Night of the Living Dead" mp4 file that was posted, so maybe that answers something. Also, as a pure side note, when I have ripped PD stuff from DVD (I use Mac, so Mac the Ripper is a nice option,) then convert to Mp4 with Handbrake it seems to work well. Just laying everything I know out there. Hopefully we can all help each other.

Reply to this post
Reply [edit]

Poster: kc0dhb Date: Nov 6, 2005 9:51am
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

drugs_are_like_that_256kb.mp4
fine (messed up movie...)
feud_maker_256kb.mp4
fine
sing_a_song_of_six_pants_256kb.mp4
completely broken
Sound and Video both broken
why_doesnt_cathy_eat_breakfast_256kb.mp4
audio dies near the end.